1. Field of the Invention
The invention relates to a device for storing and dispensing viscous substances. In this connection, viscous is understood to mean all substances capable of flow, i.e. liquid to paste-like substances, which can also be gel-like, for example. For use, the substances can be mixed from at least two components. The components themselves can also be viscous, but not all of them have to be viscous, only at least one does.
The viscous substances are, for example, adhesives or sealing materials, such as those used in dental technology. In the case of such applications, the individual components are currently stored separately, or in bottles. For use in the dental sector, only very small amounts are usually used, for example between 0.01 and 10 ml. Storing the components to be used in use in individual bottles and subsequently mixing them in a crucible or the like brings with it the disadvantage that the components are exposed to the environment before being mixed and that solvents can escape, for example, or, particularly in the case of light-cured substances, that curing already starts before and/or during mixing. Furthermore, it is difficult to meter such small amounts of substances, so that the desired mixture ratio is not precisely achieved. The substances, after having been mixed, are applied to the application site by means of a brush or similar aid, for example, thereby additionally causing the risk of contamination of the individual components stored in the bottles.
2. The Prior Art
A container for liquids in the form of an oblong, flat bag is known from DE 37 17 512 A1 (Ivers-Lee), which is divided into two compartments. Two chambers that are arranged one above the other and separate from one another are accommodated in the first compartment, while a single third chamber that is separated from the first two chambers is accommodated in the second compartment. The first two chambers are formed by two outer films and a center film, the circumferential edges of which are sealed. The first two chambers are filled with liquids that are different from one another. The third chamber, which directly follows the first two chambers, and is formed by the two outer films of the first two chambers, does not contain any liquid. The first two chambers make a transition into a tip that points in the direction of the third chamber, the sealed edges of which have a lesser laminate adhesion than that of the sealed circumferential edges. The container makes it possible to mix at least two liquids, if necessary also with a non-liquid substance. At the end of the third chamber that faces away from the first two chambers, a planned tear-open point is provided, in the form of a tear-open notch. By tearing the end part of the third chamber open at this point, the liquid content can exit from the third chamber. This known container for liquids is supposed to be used in the pharmaceutical sector, for example, or in the case of adhesives. No contamination of the liquids or the non-liquid substances can take place in the container, because the circumferential edges of the container are hermetically sealed. Because of these tightly sealed circumferential edges, no leakage of the liquids can take place, either.
A disadvantage of the known container for liquids is, for one thing, the difficulty in introducing the components to be mixed, in the production of the container and, for another, the difficulty in emptying the third chamber during handling of the container, since it can be difficult to tear off its end part, or a tool such as a knife or scissors is required, and thereby there is the risk that the mixed fluid can be splashed out. Also, two hands are required to empty the container, since it must be compressed flat to dispense the liquid, so that the liquid is not merely moved within the container. Furthermore, metering of the amount of fluid dispensed from the container is almost impossible.
A device for storing and dispensing substances, preferably liquids in small amounts, is known from EP 0 895 943 A2 (Espe Dental), which comprises a container formed by two films heat-sealed with one another, whereby the films form a chamber to accommodate the liquid, as well as a pocket for holding a brush, with one another. A planned breakage point is formed between the chamber and the pocket, in the connection of the two films, which is released by means of pressure on the chamber, so that the liquid is pressed from the chamber into the pocket and the tip of the brush located there can be wetted. One of the two films can be a deep-drawn film, and the other film can be a cover film. Instead of one chamber, two chambers, a first and a second chamber, can also be provided for separate accommodation of different substances, which are to be brought into connection with one another by way of a passage region that can be selectively opened.
In use, a connection with the second chamber is first produced by means of pressure onto the first chamber, in order to mix the two components with one another. However, mixing is not entirely satisfactory. Then the part of the device that contains the empty chamber is bent onto the second chamber in such a manner that the chambers lie on one another on the cover film, and after pressure onto the second chamber, the brush is wetted with the liquid mixture.
This device also has the disadvantage that the second chamber must be so large that it can accommodate the volume of both components. This causes either that the component in the second chamber suffers because it is exposed to air during storage, or that the free space above the second component must be filled with an inert gas, or evacuated, and this increases the production expense. In order for the bending process to take place at the right location, the two films are pulled in at the sides, in the region between the two chambers. Because of the arrangement of the two chambers in series, they have to be pressed out one after the other. In all the alternatives, nothing is said about the way the components are filled in. Because of the use of a brush as the application instrument, handling during application of the substance capable of flow onto the application site is also only possible with two hands. Furthermore, the production and storage of the device are complicated, because of the brush that is required for applying the liquid mixture.
An analysis method and a device for implementing this method are known from DE 100 34 647 C1 (3M Espe). For this purpose, the device has a pocket, an applicator, and at least one chamber containing an indicator substances and, if necessary, another chamber containing a buffer substance, whereby the first chamber can be connected with the pocket, and the second chamber, if it is present, can be connected with the first chamber and/or the pocket by way of a passage region that can be selectively opened. Also, several chambers can be present, which are connected by way of passage regions that can be selectively opened, in such a manner that all of the substances contained in them can be transferred to the pocket in serial and/or parallel manner; this necessarily is done using two hands.
Here again, the need for a special applicator has a detrimental effect on the production process, the storage, with regard to the space required, and the handling, which again, as mentioned, can only take place using two hands.
A device for storing and dispensing a composition capable of flow is disclosed by DE 100 56 212 A1 (3M Espe), having a first and a second film, a dispensing region, a first chamber containing a first substance, and a second chamber containing a second substance, whereby the chambers can be connected with one another by way of a passage region that can be selectively opened, at least one of the films in the region of the chambers is deep-drawn, and at least one of the films in the region of the second chamber is preformed or can be preformed in such a manner that after activation of the device by opening the passage region, the first substance can be completely transferred to the second chamber, thereby increasing the volume of the latter. In this way, storage and dispensing even of larger amounts of substance is supposed to be made possible, without any detrimental effect on the result of mixing.
The configuration of the second chamber in such a manner that its volume can be increased causes the production expense to be increased, and requires the use of a film that can be deformed or stretched under pressure onto the second chamber.
A dental bleaching system that merely serves for storage is known from U.S. Pat. No. 5,240,415 A (Haynie), in which heated silicic acid is supposed to be used as the basis for the production of a paste with a hydrogen peroxide solution. In this connection, the paste serves as a non-reactive carrier, in order to control the application of the hydrogen peroxide solution onto a tooth surface. The silicic acid is at first contained, by itself, in a predetermined amount, in a mixing chamber, while the hydrogen peroxide solution, in a predetermined volume, is accommodated in an ampoule. Both of them, the silicic acid and the ampoule, are accommodated in depressions, which are open towards the top, of a corresponding deep-drawn carrier, which depressions are covered with a protective film for storage.
A plastic packaging for storing and dispensing active material is known from U.S. Pat. No. 4,534,509 (Holzner), which has several compartments that are intended to accommodate liquid, solid, or gel-like material. The compartments are formed by connecting two flexible polymer films, so that at least one sealed storage compartment is present, which is impermeable for the active material, as well as a sealed accommodation compartment. At least one of the edges of the storage compartment is formed by a system that consists of an inner foam material layer and adheres to leak-proof, flexible polymer films at its two outside surfaces. External pressure onto one of the compartments causes the foam material layer to tear open, without damaging the polymer films, so that it is possible to empty the storage compartment into the accommodation compartment, without exposing the active substance to the environment. This plastic packaging is particularly useful for ready-to-use mixtures of different components, immediately before their use. It is not stated how the storage compartment is filled and the active mixture is dispensed from the packaging.
A packaging for liquid fill material, consisting of a deep-drawn part and a cover film that tightly covers the deep-drawn part from the top, is known from DE 31 22 237 A1 (Klocke), in which a liquid fill material as well as an insert part for dispensing the liquid are located in the space between the deep-drawn part and the cover film. The packaging has a planned breakage point that is placed in such a manner that when one part of the packaging is broken off the other part, the insert part is exposed, so that liquid can be dispensed through a passage channel from the space for liquid, through the insert part. This packaging is particularly intended for use as disposable packaging or also for samples of goods. By means of a suitable configuration of the insert part (brush, sponge, eyedropper, plug, etc.), the method and the speed of dispensing the liquid can be determined. This packaging, too, is complicated in its production, and requires operation with two hands.
A single-dose disposable dispensing device for several materials is known from EP 0 770 021 B1 (FIG. 16/17) (Centrix), which has a flat container element and a complementary cover element, an applicator depression, which is formed in the flat container element, and an open end, as well as an applicator that is arranged in the applicator depression and part of which extends beyond the open end of the applicator depression. In this connection, a holder device is provided, which belongs to the applicator depression, an articulation that connects the cover element with the flat container element, at least two material depressions that are formed in the flat container element, a depression gasket that is formed in the flat container element and surrounds each of the material depressions, a complementary depression gasket that is formed in the cover element for each of the material depressions, whereby the complementary depression gaskets come into engagement with the corresponding depression gaskets, in order to seal off the material that is filled into the material depressions.
This dispensing device, which is intended for medications, is also complicated in its production and difficult to handle, particularly if two components are supposed to be mixed, and these are to be brought to a mixing region of the flat container with the applicator, and mixed there.
A thin, small plastic packaging, also for liquid substances, having a metering opening that is made in it, is also known from DE 33 10 215 A1 (Flier), which is characterized in that the fill substance is packaged in an edge-sealed, i.e. edge-glued plastic bag, the lower wall of which consists of thick material, but the upper wall of which consists of a thinner material. In this connection, the thinner side of the bag is bonded or glued to a thicker film strip on its bonding or gluing edge; at the same time, a cut-profiled rod is placed between the thinner side of the bag and the film strip that lies above it, resting freely, the other end of which is rigidly connected with the film strip that continues further, so that when the pull piece of the film, which lies between the bag and the separating cut-outs that form the tear or separation location, is pulled, this end is pulled out of the part that separates, and thereby cuts the thin-walled side of the bag open, under the pressure of the film, as it passes over it, and creates an opening in the bond or glue seam between the film and the bag, at the tear or separation location, from which the fill content is caused to flow out, in metered manner, by means of pressure on the bag, and this opening closes again when the pressure is relieved, because of the material elasticity of the film and the bag.
WO 01/46037 A1 (Espe Dental) shows and describes a device for storing and dispensing a substance capable of flow, made of a top and bottom film, which form at least one chamber, a dispensing region, and a passage region that can be selectively opened and connects the chamber and the dispensing region, whereby the films are peelable in the passage region and are firmly bonded to one another in the other regions, and whereby an enlargement of the surface can be achieved at least in a partial region of the dispensing region, by means of forming waves in the top and/or bottom film, with a progression of the wave valleys along the flow direction. In this way, it is supposed to be possible to dispense even larger amounts of substance in targeted manner, simply, and without spilling, without any additional aids. In one embodiment of the device, two chambers arranged in parallel, separated from one another by a partition wall, are provided, which open into a passage region, parallel to one another, in the region of a chamber shoulder. Each of the chambers is intended to accommodate a substance capable of flow, and both chambers are separated from the dispensing region by means of a peelably sealed passage region. Furthermore, the peelably sealed passage region also separates the chambers from one another. While the two chambers have no connection with one another in the sealed state of the device, because of the sealed passage region, mixing the two substances located in the chambers is possible in the jointly provided dispensing region, after the passage region has been opened. Weakening of the passage region to facilitate opening is done by twisting the chambers in the region of the chamber shoulder, against a wing in the longitudinal direction of the dispensing region. After having been twisted back into the initial position, the passage region is sufficiently weakened so that even slight pressure onto one or both of the chambers can bring about opening of the passage region and therefore a connection between the chamber or chambers, in each instance, and the dispensing region. Furthermore, it is possible, by means of reduced pressure on one of the chambers, to dispense only part of the amount of substance contained in the chamber. In this way, it is also supposed to be possible to influence the mixture ratio of the two substances to be dispensed, but this involves difficult handling. In particular, this device also requires two-hand operation.
Furthermore, a container for separate storage of at least two products is known from DE 37 26 876 A1, which has two compartments separated from one another, and a film that seals them. In one of the compartments, which is additionally sealed by another inner film that is spaced apart from the first film, a ring-shaped insert is provided, which is provided with a row of teeth on its side facing the film. To open the compartment, pressure is exerted on the insert by way of the container wall, so that the teeth of the ring cut through the inner film of the ring, and the product can be dispensed into the second compartment. Several passage openings are provided in the insert, so that a liquid accommodated in the compartment can flow into the second compartment, where it is mixed with the base product, also through the ring-shaped insert. After the first film, which covers the entire container, is pulled off, the ready-mixed product can be removed from the second container, for example by using an applicator. Also with this container, it is not possible to precisely meter the amount of fluid transferred from the first compartment into the second compartment.